Timer mechanism



March 20, 1951 M. H. KAEFER ETAL 2,545,617

TIMER MECHANISM Filed June 19, 1946 2 Sheets-Sheet 1 35 @martin @#*Kaefev ve/Few assei't TTO man March 20, 1951 M. H. KAEFER ET AL 2,545,617

TIMER MECHANISM Filed June 19, 1946 2 Sheets-Sheet 2 44 @martin (S-(.@wlefef 45. veveH c3 asseH- 3' MXM TTONE'Y Patented Mar. 20, 1951 Martin H. lKaefer,l .Thomast'om and Everett :S, Bassett, Waterbury, Conn.,..assignors -toGeneral 'Time Corporation, a corporation of .Delaware AApplicati'orrJ une '19, 1946', Serial No.677,68-7

(Cl. :1:61-1)r 13 Claims.

.This invention vrelates :to timing `mechanisms and v:more particularly `to :a mechanism wwhich includes an .automatically :operated lelectric switch 'for energizing an :electrical load during a .predetermined time interval.

Such devices may be zused vin -timers Tfor kitchen ranges or other controlling "means .for electrical cooking :appliances wherein .the circuit .to the cooking velement closed Vat a predetermined time and opened at a later ltime. lFor other uses the parts maybe :so arranged 'as to .cause the :load to be :deenergizedonli7 during the lpredetermined interval.

Range timers `in rorder to 4be lpractically useful must :be provided with an :easily understandable control .means. Otherwise Ithe Aaverage :housewife 'will nd it easier to do without the range timer than ito understand its foperation. It vis desirable to vprovide :a `range Ltimer with controls which .may beset l.in yany order and .which will clearly indicate vboth the nurationof the :cooking Vperiod as well :as vthe time in .which fthe cooking period .is Y-to startandto'cease. -It-is also desirable ".to providea'control inwhich :the active adjustment serves to place lthe switch and its associated operating mechanism into la proper initial condition. In order to prevent inadvertent operation of the timer during a succeeding twelveA V"hour period itis further desirable that the control `be self-deleted; that is tosay, after l tion,.and which is providedwith legibleandeasily adjusted 4Control means.

.It is another. object of the `invention to provide improved time responsive .means to vactuate electrical contacts at a predetermined time vand to restore `the same to their original Yposition .at a 'later time.

A further object vof the invention :is to 1provide an improved ltime .switch wherein the -controls .are self-deleting :and vin which the unexpired portion fofthe cooking. period may be read at Va glance.

Still another lobject of the invention .is `to 'produce Va timing mechanism utilizing a spring :biased detent in which the frictional forces exerted upon the .timing lmechanismloy the detentare 'of ia balanced nature during the fp'eriod .2 .that :the ".au't'omatic timing ffunction ibeing used, and 'in :which 'such :frictional :forces :are :completely FJen-nnoved during` non-use not the :automatic timing function.

It is a .still :further robiectiof Lthe invention to lprimi-de atiminglifnechanism in Iwhich .thefswitch and the1zsw'rtch foperating parts are .placediin an initial :or .cocked 'position vautomatically upon the setting of the time @adjusting means.

'Other objects 4and vadva'rniages lof the :invention :will .loe apparent iiromv thezfollowing .detailed description .taken 1in connection with .the .-accompanying fdrawings, in which:

Eigure l1 is a A'front velevation showing -the erf-'- ternal 'appearance .of .a .timingzmechanism constrnctedv :in accordance with :our invention,` bthe .controls :being set 5in'. this instance ito energize .the 4load liat 10:':30 -foclo'ck and to :deenergize the load zat 11:55 foclock.

.Eig.12 -is .a rontfelevationwith the .faceaof Pthe mechanism .removed in 'order .tofshow the means oridriving thetinie setting disks. y

:FigJS is avertical `section -taken'ealong the .line :3--3 :of 2 to show :the internal operating mechanism.

Fig. 14 shows Athe position-A of Athe .switch voperating-detent iin relation -to the atimer discsat 8:30

.o-clock. l M n Fig. .5 shows the position-of .the detent' .of .4 .at 10:30 '01clock, A

.'Fig. 6*.-shows the positions of -.the ide'tent .and associated timer -discs .at l1 z 55 .oclocle Fig. '7 .is va horizontalsection .taken valong 'the line 'l-,1eofl!ig.-3.

Fig. 8 is a detailed .view of the switchandlco'ntrolling :toggle mechanism. A

Eig. v9 is Y`a fragmentary .pferspedtiize viewlin partial .'sectionfshowing fthe' detent and associated timer discs together vwith the switch operating mechanism.

Whilezthe invention .is susceptible ,o'f' various modifications and .alternative constructions .and uses, `we 4have shown .in `the .drawings .and will hereindescribe Adetail one .embodiment-of the invention. lt is Vto -be understood, fliowever, .that ,we do not intend to limit .the invention bysuch disclosure, but aim to .cover Vall modifications-,and alternative constructionsand Auses .falling within `the spirit Mandescopeof v.the,invention.as'expressed in the appended claims.

Prior .art timers for controlling I.electric ranges and the like .have Yloeenfrelativelycomplex, thus making vthem bothdiicult and expensive to manuf-acture 'and complicated to use. -Such 'complication has been .overcome.-and a .number .of radditional advantages derived by application of the teachings disclosed herein'. By way of introduction, in accordance with our invention a rotatable time driven member carres a biased detent. Placed in the path of movement of such detent are two coaxial discs rotatively coupled to time setting dials on the face of the mechanism, such dials being respectively adjustable to indicate an on time and an off time. The discs are adapted to engagedly receive the detent in succession as the time driven member brings the detent successively into registry with the discs. Movement of the detent, when the latter is received by the nrst disc, is utilized to turn the switch to the on position. Subsequent movement of the detent, upon being received by the second disc, restores the switch to its off position.

The external appearance of the mechanism and the means for adjusting the time setting components are shown in Figs. 1 to 3. It will be seen that the timing device, when enclosed in a housing I0, closely resembles a conventional clock and is of approximately the same size. Clock hands Il and I2, driven by a timing gear train to be discussed, cooperate with graduations or indicia I3 which may be imprinted about the periphery of a transparent iixed dial I4 to indicate the time of day. Numerals corresponding to such graduations may, if desired, be imprinted on a retaining flange or bezel I5. The transparent cover glass I6, which may be apertured at the center to receive a hand setting knob I8, is retained by the bezel I5 in position to protect the clock hands and to improve the appearance of the device.

Arranged coaxially behind the transparent fixed dial I4 are two time setting dials 2l) and 2 I. rIhe dial 2U, also referred to as the start dial, is adjustably rotatable by an adjusting knob 22 to indicate by a pointing index I9 the time at which the current will be applied to the load. The dial has an annular aperture or window 23 near its outer edge which lies adjacent the index I9 and, in the present embodiment, extends halfway about the periphery of the disc. window exposes to view a corresponding portion of the second or stop dial 2l. The latter has a pointing index 24 which is adjustable in relation to the time scale by an adjusting knob 25. Adjacent the index 24 are graduations 26, a portion of which are obscured by the time setting dial 20. During operation of the device the visible graduations are a convenient indication of the time interval that the range or other connected device is to be operated.

As shown in detail in Fig. 2, the adjusting knob 221s rotatively coupled to the start time setting dial 25 by means of pinions 28 and 35, which engage a rack SI at the periphery of the dial. In like manner the adjusting knob 25 is rotatively coupled to the time setting dial 2l by pinions 32 and 33 engaging the rack 34 at the periphery of the stop time setting dial 2I. The idler pinions and 33, respectively, are used to cause the time setting dials to rotate in the same direction as the adjusting knobs 22 and 25, which is a convenience in adjusting the dials. As later discussed, the adjusting knobs 22 and 25 must be axially depressed before engagement of the associatedpinions takes place, such axial movement serving also to effect cooking of the switch contacts into an initial oi position.

Also accessible from the front of the device is a manual switch operating knob 35 which may be used to override the automatic control of the This electrical switch to place the range or other load in the on condition. In the present instance the latter knob is rotatively coupled by a shaft 3i (see Figs. 2 and '7) to a crank 36 which has switch operating plungers 38 pivotally mounted at its periphery. The plungers engage switch leaves 40 carrying movable contacts II I .y Stationary contacts 43 resiliently mounted on switch leaves 44 cooperate with the movable contacts 4I to control the electrical circuit. II desired, two separate loads may be simultaneously energized or alternatively the contacts may be wired in series or in parallel, depending upon the current and voltage characteristics of the load.

Clock mechanism The clock mechanism, in other words, the motor, time indicating hands and interconnecting gears, as such, form no part of the present invention except to the extent that the driving gear train cooperates with the automatic switching portion of the mechanism. As shown in Fig. 3 the clock mechanism is included in a frame indicated generally at 45. A motor 46 mounted on the frame and which is preferably of the synchronous alternating current variety drives a train of reduction gears 4B to move'a central shaft 50 at a rate of one revolution per hour. The shaft 5@ extends through to the hand setting knob I8 and carries the minute hand l I.

Also mounted on the central shaft 50 is a pinion 5I which drives a gear wheel 52 mounted on a shaft 53. The latter shaft carries a pinion 54 which, in turn, drives a rotatable member 55.

i. In the present instance this rotatable member consists of a gear wheel having apertures therein to receive detenting mechanism for the operation of the time switch to be later described. An hour hand sleeve 58, which may be rotatively fixed to the gear wheel 56 by any desired means, surrounds tlie central shaft 5D, extending forwardly within the clock body to engage the hour hand I2. Because of the speed reduction brought about through the use of pinion 5I, gear wheel 52, pinion 54 and gear wheel 55, the hour hand moves, as is conventional, at 1/12 the speed of the minute hand.

Switch operating detent mechanism In order to understand fully the operation of the detent mechanism used to operate the electrical contacts, reference should be made especially to Figs. 3 and 9. Means are provided for successively engaging apertures in two manually positioned discs as the detent is rotated successively into registry therewith, the axial movement of the detent being utilized for switch operating purposes. In the present embodiment the engaging means is a detent Gli mounted on a rotatable collar 6I, the latter being freely slidable on the shaft 50. Axially extending end portions 62 and 63 of the detent engage apertures 64 and 65 in the rotatable member 56. Thus as the rotatable member 56 rotates once every twelve hours, the detent 6U, being in engagement therewith, is driven at the same speed.

The detent 6I! is urged forwardly within the clock housing by the biasing force of a spring 56 mounted on a bracket 6'! and. acting upon a follow-up member 68. In the present instance the follow-up member G8, the movement of which controls the switch, is pivoted to a cross member 67 of the clock frame 45 by means of a pivot which may, for example, include dowel-like extensions 'I engaging cooperating holes in the '5 cross lmember. -Joint axial Imovement fof lthe follow-up member l68 and-the detent 360 results from the 4interference 'between .the edges of laperture 'H and `flanges 12 on -the collar 6l.

The switch mechanism to be Vlater fd'etailed is mounted iin the lower '-portionof the housing t0 remotely from the pivotedendrof the follow-.up member 68. Becauseof fthe .pi-voted 'nature of the follow-up member :and because of the relative location of the detentandiswitch mechanism, the follow-up member 68 -serves as a `displacement multiplying lever. Thus very .little axial movement of the detentiis.required'torproduce appreciable movement of the [remote Ior switch end of the follow-up member 68.

Placed .coaxially with fthe .time driven .member 56 Aand -in ithe -pa'th .of .axial 'movement :for 'the detent 60 are two detent .receivingzmembers F13 and T4. These membersmaylbe .conveniently -reerred to as timer discs. 'The .rst-ofsuch discs, 13, .is fixed to a bushing 16 .which also .has xed to it the time setting .dial 2.0. In like manner the timer disc 'Misfastenedltoa bushing .18 which has iixed 4to it the remainingftime setting dial 21H. Provision is made for receiving the detent :as .the detent is bodily rotated .into-a position of registry. In the present instance ythe .end'portion .S3 of the detent is received in apertures or .notches-.'80 and 8:1 itFig. 4') locatedat the kperipheryiof the 'discs 13 and 14 respectively whileapertures 82 :and 83 serve to receive the end portion 62 Vof the detent. It is to be noted that each of the end portions 62 and 63 of the detent engage the respective apertures at the same time, `thereby causing 'the detent Yto be Yreceived bythe discs bcthrabruptly and positively.

With vthe detent 16D engaging the `timer Adiscs 73 and le as shown -in.Eig..3, .itfwill .beapparcnt that the discs will rotategin ,unison'with the movement of the datent .and .the time driven member 56. Under :such conditions Anoerictional load will be :placed on 'the driving mechanism vsince the bushings 'I6 and 7:8 `will .be .rotated vprecisely .in step with the movement of the central bushing 53 leading to the Vhour hand iLZ. The latter condition exists after the automatic switching mechanisrn .has completed Yits "function and the clock is 'in 'the vfree running condition.

The condition of :the 'mechanism kprior to A'the performance of an automaticswitching'operation is illustrated in Fig. V9. In this 'figure it 'is seen that the detent 56 has been cocked A0zretracted out of engagement with thetimer discs 13 `and lll. Further, the apertures 35, 8i are out of Yregistry with the end portions 62, .53 ofthe detent. Under such vcircumstances the end portions of "the detent are vurged into resilient frictional engagement with the disc '13. Because of the'axial pressure between the detent andthe'timerdisc i3, the line Aof action of lwhich is spaced from the .axis of the disc, there isa tendency of the .detent to produce an unbalanced ior'tilting force `perpendicular to the disk. An 'unbalanced force of this nature is obviously undesirable because of lthe resulting Vincreased Wear and increased frictional forces. In the present embodiment 'such unbalance has been substantially eliminated by the use of the two end portions 62 Vand 63, since ,thelatter are located on opposite sides of the axis and at approximately the same distance therefrom. Thus the forces applied perpendicular `yto the disc 'I3 are substantially balanced and tendency for the disc to tilt i practically eliminated. Because the detent 69 is double ended, theendportions '62 .and 63 are located atdiierentdistances from Athe 6 axis. and onlyone vpositionfoi registny lexists :duri inga twelve hour time cycle.

Upon passage of time, the time .drivenamember 56 causes bodily rotation .of -the detent 60 to a point at which the end portion 63 of the detent is received -in the notch-V80 andthe remainingend portioni' is received in -the aperture 82. As this occurs the detent, under the urgingaction of the springe, Jmoves axially, the ends ofthe detent successively engaging -the 'presentedsurfacefof the disc lll. 'The'latter movement of the Ydeten't `is caused toV complete the circuit and thereby "to energize the'load. Subseduentlrotaitive movement of the detent Will bring the end portions "62 "and 63 into `registry with 4the apertures 83 zand -81V respectively, whereupon the 'detent suffersl further axial movement. The latter' movement, 'as Willbe seen, is utilized 4to'restore the switch .tothe open position 'thereby deenergizing the load.

t will be noted that prior L.to engagementby the d'etent the 'time setting dial ZD'jtheattac'hed bushing zl, and the associated 'timer disc'll are freely rotatable. It would seem, therefore, `that there may be danger of the time setting dial '20 f' rotating undesirably because of `the.frictionalurging action of the end portions '62' and .63 'on "the presented face of the timer vdisc lf3. However, means are provided for preventing such rotation.` It will be noted irom'Fig. `3 that the time setting um .2e engages an abutment@ rings. :2 andai placed at the yperiphery .of the dial Ito limit :the axial outward movement. Since a certain amount of axial play exists between .the inter-f -fitting bushings 58', 'i6 and 1.8,lsubstantially tlie full axial 'iorce of the .detent lis `counteracted by pressure oi the dial 2li? against the abutment '8"l. Such pressure results in .friction which -res'is'ts turning movementof .the timesetting .dial .as long as axial force is exerted thereon b-y the detent. Since the abutment 84 is at a greater .radius than the end portions 62 and .63 of the detent, .the fricticnal torque lpreventing Ymovement Yof the time setting dial 2E] always exceedsthe .frictional drag tending vto .produce rotation thereof. .Thus the dial 2d .remains stationary -at .all times.

It is to be noted that after the detent .slpasses through the timer disc 73, the resisting force exerted by the abutment 84 is reduced to `zero and the time setting dial 20 thereuponbecomes iree'ly rotatable with the clockdriving mechanism. The automatic removal of such frictional load ibecomes especially rimportant .in View of the low power rating of the rconventional clock motor. Rotation of time setting .dial .21, the attached bushing 1.8 and the associated timer Vdisc iii Vis prevented in like .manner .'by an additional abutment 86 located at the periphery of the dial. Preferably a plurality of such abutments 84 and 86 spaced equally about the periphery are used to eliminate unbalanced forces .on -the bushings associated wth'thetime setting dials.

As a specic example of the relationship which may exist between the detent and the associated timer disks, reference is made 'to'Figs 4, 5 and 6. Let it be -assumed that the time is l813() oclock, that the cooking operation .is -to begin at .10.:30 and to stop at 115.55, the settings corresponding .thereto Ybeing shown in Eig. 1. .At 8:30 (Eig. 4') the .detent 6U, although contacting the back of disc v13,.is in rotative engagement with neither of the timer discs. At "10:30 Fig.'5) the detent has moved into registry with vthe apertures` 8B, 8'2 of the disc 73 and the resultant faxialniovement turns the switch to the on position. At il-:'55 (Fig. v6) the .detent160 comes, into 'registry with the apertures 8 l, 83 and the resultant axial movement of the detent causes the switch to be restored to the 01T position.

Switch structure In the practice of the invention switch means are provided for enabling the switch to be initially in the oli position, for enabling the switch to be closed upon movement of the follow-up lever 68 to an intermediate position, and for enabling the switch to be reopened upon further movement of the follow-up lever in the same direction. In the present embodiment this is accomplished by a toggle mechanism. As shown in Fig, 9, the follow-up lever 58 is terminated in a shaft-like extension 88, such extension engaging the follow-up lever at points Sii and 9i. The portion of the extension 8&1 intermediate the points of support 9c, 9| is made accessible by an aperture 92 in the follow-up lever $8 for a purpose to be described. At the end of shaft 88 are pivotally mounted toggles 93, Sli. These toggles have pin-like extensions 9&5 and 98, respectively, which engage apertures HB8 and itl in the switch leaves 40 (Fig. 8). The switch leaves it and iti are anchored in blocks or" insulation 9i and are terminated in binding posts 8l, ttl for connection of external wiring.

The length of the toggles 93 and Si is such that prior to engagement between the detent @il and the disc 'i3 (Fig. 9), the toggles are in an oil"- center condition. Under such circumstances the spring leaves 40 are in the innermost position, and since follow-up movement of the contacts on leaves 44 is limited by retaining edges "iii, the contacts are accordingly open. Subsequent move- Sil ment of the detent into engagement with the disc 13, however, causes the toggles 93, ed to be rotated into the dead-center position illustrated in Fig. 8. Such movement forces the spring leaves 4| outwardly and Contact is made between contacts 4| and 43. Next, movement or" the detent into engagement with the timer disc i4 causes outward swinging of the extension 85 of the follow-up lever |58, reverse folding of the toggles 93 and 94 and consequent separating of the contacts.

Since the spacing of the time discs i3 and lil is normally quite close, only limited axial movement of the detent occurs as the detent is received by the recesses in the discs. However, the distance multiplying action ci the follow-up lever 68 insures that adequate toggle actuating movement is produced. The use of a toggle has been found ideal for operating the electrical switch, since continued movement of the toggle actuating shaft S8 in the same direction causes the circuit to be made and subsequently broken. Furthermore, because of the nature of the tcggle powerful leverages are available as the toggle moves into the vicinity of the dead center position, further insuring the high contact pressures particularly desirable in the case of ranges having a high current drain.

Automatic cooking mechanism It is necessary in connection with detent operated switches that means be provided for cocking the detent into an initial position and for concurrently placing the switch contacts in a desired initial condition. In accordance with our teachings this is done automatically as an incident to the setting of the time setting dials. In the present embodiment axial movement of the adjusting knob 22 is necessary to engage the associated pinons 28 and 3B thereby to set the dial :TIO

2D to the desired position. As shown in Figs. 3, and 9, the knob 22 is attached to a shaft |02, which is slidably mounted in apertures |09 in the frame and which -extends through apertures |03 in a bracket |01. Axial movement of the shaft results in rearward movement of the bracket |01 because of the presence of a pinned washer |4` or similar obstruction on the shaft m2. The bracket ll is loosely pivoted to a horizontally extending resetting lever l by any desired means, for example, by a dowel and socket joint |98. Inward movement of the bracket |01 therefore causes inward movement of the resetting lever |66 about a pivot |Il mounted on the clock frame.

At the free end of the resetting lever |06 is a rearwardly extending projection having provided therein a notch ||2. As shown in Fig. 9, the projection l i is positioned to extend through the aperture 92 into engagement with a portion of the shaft-like member 38. The engagement between the smooth surface of the latter member and the smooth internal surface of the notch insures substantially rictionless pivotal engagement at this point. From the foregoing it is obvicus that inward movement of the knob 22 to the position shown in Fig. 7 or 9 is eiective to cause inward swinging of the follow-up lever 68, compression of the detent spring 66, withdrawal of the detent @li from the discs 'i3 and 'i4 and the opening of the contacts 4|, 43. Inward movement ot the knob 22 is also effective to engage the pinions 28, 36 as previously seen, and subsequent rotation of the knob 22 is effective to move the time setting dial 2|) (and therefore the timer disc Ki3) to any desired position.

The foregoing discussion has considered the resetting mechanism associated only with adjusting knob 22. It is to be understood, however, that substantially identical mechanism is used in connection with the adjusting knob 25 and for the same purpose. Corresponding reference numorals are used in each instance.

Summary of operation Prior to use of the timing mechanism the detent ill will normally be in engagement with the discs 'i3 and I4, and the associated time setting ydials 2Q and 2| will be subject to free rotation with the hour hand I2 of the clock mechanism. To set the start dial it is necessary to apply inward pressure to the adjusting knob 22 which produces rearward translation of the bracket |01 and rearward rotation of the resetting lever l about the pivot It. The resulting pressure applied to the lower end of the follow-up lever 68 removes the detent from the discs 73, i4 against the bias of the spring 66 and opens the switch contacts 4|, 43. Rotation of the adjusting knob 22 is thereupon effective to rotate the start time setting dial 2U to any desired position, for examplej the 10:30 oclock position shown in Fig. 1.

'Io adjust the stop time setting dial 2| inward pressure is applied to adjusting knob 25 and the knob is rotated to bring the stop time setting dial to the desired position, for example, 11155 oclock.

Upon passage of time, bodily rotation of the detent @t occurs until at 10:30 oclock the detent engages the apertures te, 2 in the disc 73, the resulting axial movement of the detent causing the switch contacts to close. Since the detent 6B is then in positive engagement with the timer disc 13, this disc and the attached time setting dial 120 willrotategwith thefhour hander theielock. Thus ther indiciaf 26;; will` be.y gradually, covered, the uncovered graduations; being; ai measure of the4 time` yet; remaining in thecooking. period. Einally,;at 1l: 55- ocloel -1the,-.detent.,willcomeinto registry with; the, aperhires;t 8 0, 33; of; disc- T4, and the resultant axialv movement oi'the detent will cause, the switch contacts;I to be,` opened, ending the; cooking period.; Subsequent, rotationl of: the clock1mechanism=Willgoause the; timo1setting dials 29, 2| to;b erotated'w-ith thefhourf-hand. Thus the setting of the time interval is automatically deleted and willl not;n be: repeated' asi the hour hand; goesi` through; a, sueedng; twelvev hour cycle.

1. Ar timing mechameau;` comprising a time drivenY rotatablc-ih member-r, an; eccentricallydisposed: detent mounted.` fpr,- rotation therewith, means biasing saidkdetentrion axialmovement, a start: disc: mounted coaxial-ly with-,saidrotatable member inthe;z path oi biased movement of said detent and having an; aperture to receive said detent in` rotative engagement upon: rotational movement oi said detent intofregistry therewith so-that saidgdisc is; rotated; by saidtime driven member, a stop'discmounted coaxiallywith said start disc-andhav-ing an aperture to receive said detent uponadditional rotation thereof,k a switch,

an operator forsajdlswitch,saidlswitch operator beingcoupledito-said1detent and responsive to successive,` movementv thereoif fori operating; said switch; v

2. A timing mechanism@ comprising a time driven rotatablemember, an, axiallyybiased-,de-

tent mounted for bod-ily rotation therewith and spaced from the-axis thereoia first detentmeceiving membermounted coaxially with, said rotatable member for receivingsaid detent and being rotated thereby uponsaid'deteht movinginto aposition oi registry therewitha:second-,detent receiving member mounted coaxially with said rotatable, memberfor receivingi said; detent and being rotated thereby upon successivemovement of said detentinto a-,positionof registry therewith, a pivoted memberengagingsaiddetent a switch,A and a switch operatingtoggle engaging said pivoted membercand; movable` therewithfor operating; saidV switchfas saidA detent moves into successive4 engagement with said detent receiving membersr 3. A,V timing: mechanism; comprising a time driven rotatable memberran axially biased detent mounted jf orbodily: rotation therewith, and spaced from the axis thereof, a rst detent receiving member mounted coaxially. with said rotatable member for receiving. said detent andl being rotated thereby upon said detentmoving into a position of registry therewith, a second detent receiving member'rrlountedcoaxially` with said rotatablev member for successively receiving said detent. and4 being rotated'thereby upon saidl .detent moving into a positionof. registry. therewith, atoggle connectedto saidldetent andmovable into dead-center position, as said'- detent moves into .registry with said iirst4 detentreceiving member and'beyond deadfcenter position as said detent moves into registry with said'second detent receiving member, and a switch operated by said toggle and arranged to be in closed position only with said toggle in substantially deadcenter position.

4. A timing mechanism comprising a time driven rotatable member, an eccentrically disposed detent axially slidable therein, a start disc 10 mounted. coaxially with saidv rotatable` member inthe pathof` movement of saiddetentandhaving an4 aperture v to receiveY said detent ,upon rotational movement: of saiddetent` into registry therewith, a stop diskmounted-,coaxially with said start' discand having an aperture-to-receive said detent upon additional rotationthereof, a toggle` responsivetoyaxial movement of said detent upon successive reception; thereof by said discs, movement4 of said detent intoA a received position in said start disc being `eiiectiveto'move said toggle into dead.-center position, a= pair of contacts inounted-oneach sideof said toggle and adaptedfto be operatedthereby, both of said-contact` pairs being inthe closed-position whenrsaid toggle is on dead-center butbeingin the:V open position when: said toggleis oneither sideV o deadcenter. v

5.1A timing vmechanism comprising a time drivenvrotatable member, detent means, a spring forbiasingfsaid detent means, means supporting .said detent means.y for-arcuaterotation withsaid time driven member, a nrst rotatably positioned member coaxial withsaid detent supporting member for-receiving said detent means upon said detent means-movinginto afposition of registry therewith, a second rotatably positioned'y member coaxial with saiddetent supporting member for--receiving said detentmeansupon said detent means moving intov a successive position of registry therewith, a switch operated by the movement of vsaid detent meansfresulting from the, reception thereofl by said detent receiving; means, and means for causing'rotationlof each oisaid detent receiving means in unison with said detent after reception of said detent.'

6. A timing mechanism comprisingv first and second time setting dials, a time driven rotatable member, an axially biaseddetent mounted for bodily rotation by said rotatable member and spaced from the axis thereof, irst and second detent receiving members mounted vcoaxially -with said rotatable member and arranged forthe successivefreception of saidy `detent upon said detent coming intoV successive registry therewith, and means for coupiing-said dials tov said detent: re.- ceiving membersior movement of said-dials in unison therewith upon respective:V engagement by said-detent;

7. AA timing mechanism comprising aitime driv'- en, rotatable, member, an axially biased detent eccentrica-Hy mounted` for Ybodily rotation by said rotatable member, rst and second timer discs mountedrcoaxially;V with -said'rotatable member. in the pathY ot movement of said detent, manually positioned time setting dialsv coaxially flxedto said timer discsgrespectively for, movement therewith, said timer dises having-apertures-for successive rotativeengagementby said detent as said detentmovesA into respective registry therewith, said discs being manually positionable by rotationV of the associated time setting dials to provide a predetermined angular relationship between said apertures, rotative engagement betweenl said detent and said rst` timer disc upon movement of saidtime-driven member beingfeffectve graduale ly to bring said dialszinto-al condition of alinea ment.

8. A timingmeehanism, comprising aatimeI driv.-v rotatable member, an axially biased detent eccentrically mounted with respect to said member for bodily rotation therewith, a timer disc mounted -coaxially with said rotatable member in the path of movement of said detent and having an aperture for the insertion of said detent upon said detent moving into registry therewith, said detent being in resilient frictional contact with said disc prior to insertion, a flange mounted for axial and rotative movement with the said disc, a stationary axial abutment arranged to frictionally engage said flange and to prevent axial movement thereof under the urging of said detent, the release of axial detent pressure upon the insertion of said detent into said aperture causing the removal of pressure from said abutment and enabling substantially frictionless subsequent rotation of said disc.

9. A timing mechanism comprising a time driven rotatable member, an axially biased detent eccentrically mounted with respect to said member for bodily rotation therewith, a timer disc mounted coaxially with said rotatable member in the path of movement of said detent and having an aperture for the rotative engagement of said detent as said detent moves into registry therewith, a time setting dial coaxially fixed to said timer disc for movement in unison therewith, an axial abutment mounted at the periphery of said time setting dial to limit axial movement thereof caused by the force of said detent on said disc, said abutment being located at a suicient radius from said axis so that the torque resisting rotation of said dial and caused by frictional contact with said abutment exceeds the torque of the frictional drag of said detent on said disc.

10. A timing mechanism comprising a time driven rotatable member, an axially biased detent eccentrically mounted for bodily rotation with said member, iirst and second detent receiving members mounted coaxially with said rotatable member in the path of movement of said detent and having apertures respectively for the successive engagement of said detent as said detent moves into registry therewith, a switch, a toggle for operating said switch, a follow-up member coupled to said detent for axial movement therewith and coupled to said toggle for operating said toggle from a rst position in which the toggle arms are at an angle with each other, to a second position in which the toggle arms are approximately in a straight line and then to a third position in which the toggle arms are again at an angle, means for rotatively adjusting said detent receiving members, and means associated with said adjusting means for moving said detent out of engagement with said detent receiving members and also moving said follow-up member and toggle to said rst position prior to rotative adjustment ofl said members.

11. A timing mechanism comprising a time driven rotatable member, an axially biased detent eccentrically mounted for bodily rotation with said member, rst and second detent receiving members mounted coaxially with said rotatable member in the path of movement of said detent and having apertures respectively for the successive engagement of said detent as said detent moves into registry therewith, a switch, a toggle for operating said switch, a follow-up member coupled to said detent for axial movement therewith and coupled to said toggle for operating said toggle from a iirst position in which the toggle arms are at an angle with each other, to

a second position in which the toggle arms are approximately in a straight line and then by further axial movement in the same direction to a third position in which the toggle arms are again at an angle, adjusting knobs for rotative adjustment of said detent receiving members, and means associated with said adjusting knobs responsive to axial movement thereof for moving said detent out of engagement with said detent receiving members and also moving said toggle to said rst position prior to rotative movement of said member.

12. A timing mechanism comprising a time driven rotatable member, an axially biased detent eccentrically mounted for bodily rotation with said member, first and second detent receiving members mounted coaxially with said rotatable member in the path of movement of said detent and having apertures respectively for the successive engagement of said detent as said detent moves into registry therewith, said detent receiving members being adapted to be driven by said detent upon engagement therewith, a member pivoted at one end and connected to said detent at a point between the ends of Said member, a toggle having its arms pivoted on the other end of said memberfand two pairs of contacts biased to open and adapted to be closed, one pair by each arm of said toggle when said toggle is in a substantially {dead-center position.

13. A timing mechanism comprising a time driven rotatable member, an axially biased detent eccentrically mounted for bodily rotation with said member, first and second detent receiving members mounted coaxially with said rotatable member in the path of movement of said detent and having apertures respectively for the successive engagement of said detent as said detent moves into registry therewith, a member pivoted at one end and connected to said detent at a point etween the ends of said member, a toggle having its arms pivoted on the other end of said member, two pairs of contacts biased to open and adapted to be closed, one pair by each arm of said toggle when said toggle is in a substantially deadoenter position, a iirst rotatable shaft for setting said iirst detent receiving member, a second rotatable shaft for setting said second detent receiving member and means 'connecting said rotatable shafts to said toggle so that said toggle may be placed in its open position by the'A axial movement of either rotatable shaft.

MARTIN H. KAEFER. EVERETT S. BASSETT.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS Number Name Date 1,081,402 Porter Dec. 16, 1913 1,357,726 Richter Nov. 2, 1920 1,935,232 Smith Nov. 14, 1933 2,145,083 Dynes Jan. 24, 1939 2,300,950 Lux Nov. 3, 1942 2,310,527 Hutt Feb. 9, 1943 

